The electronic payment processing industry has been in existence since the 1960s, and it has developed a set of protocols and processes unique to its own transaction requirements. The protocols were defined long before there was any consideration of using the Internet or its related protocols for commercial purposes. Because of the criticality of payment transactions, the overriding processing application design goal was the ability to monitor the system, and to ensure compliance with strict service level agreements (SLAs). Thus, the transaction systems use point-to-point communication methodologies, and they require the ability to maintain an always-on communication session.
The Internet uses a suite of protocols that work at various layers of the Transmission Control Protocol/Internet Protocol (TCP/IP) reference model. TCP is a session-oriented protocol that maintains state during application communication in order to guarantee once-and-only-once transmission of data. IP is a non-session-oriented protocol that provides a hierarchical address space for entities on diverse inter-connected networks to pass data to each other. In order to meet the functional requirements of legacy transaction processing systems while using an Internet Protocol-based network, the various applications used by financial entities required persistent TCP sockets—which are sessions between two endpoints that are defined by each of the peers' network and transport addresses—to be open at all times. Thus, the applications instruct TCP to create and permanently keep open a socket for information delivery between two endpoints.
The use of persistent TCP sockets provides for easy monitoring of the usability state of a communication session between two hosts. Unfortunately, persistent sockets also prevent the use of newly-developed availability and scalability measures. They also don't fit into the modern Electronic Commerce paradigm.
Electronic Commerce (e-commerce) is an information technology concept that has caught on with businesses en masse since the emergence of the commercial Internet and the World Wide Web. Because the original intended use of the World Wide Web was to share documentation and other text-based information seamlessly across a diversified and heterogeneous inter-network of computers, the protocol developed to support the web—the Hyper-Text Transport Protocol (HTTP)—had portability, point-to-multi-point operation, and speed of moving from one connection to the next as its major objectives. HTTP has become the foundation for all web sites, whether those sites are commercial, academic, or personal in nature. Following the four-layer TCP/IP communication model, HTTP is an Application Layer protocol. HTTP specifies that the transport—TCP socket—should be dynamically built and torn down for each application request.
Therefore, conventional electronic payment transaction processing systems fail to fit into the modern e-commerce paradigm, and they fail to support the technologies that make high-availability and scalability possible.
Accordingly, there is a need for a new generation of network-based electronic payment transaction processing system.